Alan Rickman attends the World Premiere of Harry Potter and The Deathly Hallows - Part 2 at Trafalgar Square on July 7, 2011Getty

Oscar-winning actress Emma Thompson has led the tributes to her long-time friend, and Harry Potter co-star, Alan Rickman, following news of his tragic passing. The British actor died on Thursday (14 January) after losing his battle with cancer. He was 69.

In a statement, the 56-year-old Love Actually actress described her fellow thes as "the finest of actors" and the "ultimate ally". Other members of the Harry Potter cast and crew paying their respects include Emma Watson, who played Hermione Granger in the wizardry franchise, and Daniel Radcliffe, best known as Harry Potter.

Daniel Radcliffe

"Alan Rickman is undoubtedly one of the greatest actors I will ever work with. He is also, one of the loyalest and most supportive people I've ever met in the film industry. He was so encouraging of me both on set and in the years post-Potter. I'm pretty sure he came and saw everything I ever did on stage both in London and New York. He didn't have to do that. I know other people who've been friends with him for much much longer than I have and they all say "if you call Alan, it doesn't matter where in the world he is or how busy he is with what he's doing, he'll get back to you within a day.

"People create perceptions of actors based on the parts they played so it might surprise some people to learn that contrary to some of the sterner(or downright scary) characters he played, Alan was extremely kind, generous, self-deprecating and funny. And certain things obviously became even funnier when delivered in his unmistakable double-bass.

"As an actor he was one of the first of the adults on Potter to treat me like a peer rather than a child. Working with him at such a formative age was incredibly important and I will carry the lessons he taught me for the rest of my life and career. Film sets and theatre stages are all far poorer for the loss of this great actor and man."

"Today a friend, a role model and a truly amazing person lost his battle. I have so many good memories.#Always #RIPAlanRickman".

JK Rowling

"There are no words to express how shocked and devastated I am to hear of Alan Rickman's death. He was a magnificent actor & a wonderful man. My thoughts are with Rima and the rest of Alan's family. We have all lost a great talent. They have lost part of their hearts."

Emma Watson

"I'm very sad to hear about Alan today. I feel so lucky to have worked and spent time with such a special man and actor. I'll really miss our conversations. RIP Alan. We love you"

"Alan was my friend and so this is hard to write because I have just kissed him goodbye.

What I remember most in this moment of painful leave-taking is his humor, intelligence, wisdom and kindness. His capacity to fell you with a look or lift you with a word. The intransigence which made him the great artist he was—his ineffable and cynical wit, the clarity with which he saw most things, including me, and the fact that he never spared me the view. I learned a lot from him.

He was the finest of actors and directors. I couldn't wait to see what he was going to do with his face next. I consider myself hugely privileged to have worked with him so many times and to have been directed by him.

He was the ultimate ally. In life, art and politics. I trusted him absolutely.

He was, above all things, a rare and unique human being and we shall not see his like again."